Tonight, Steven Spielberg takes us back to the land of dinosaurs. How crazy will Terra Nova be? We'll find out over the next few weeks. But it can't possibly go as bonkers as some of television's other dinosaur shows. Here are our picks for the most demented dinosaur-centric TV shows in history.

Forget the gene splicing of Jurassic Park — the best dinosaurs in science fiction are hyper-evolved reptosapiens or confused, time-displaced beasts. Here are 20 fantastic saurians who just wouldn't go extinct.